US1610462A - Trolley hoist - Google Patents

Description

Dec. 14 1926. 1,610,462

.1. MATTHEW$ON ET AL TROLLEY I-IOIST Filed July 11, 1922 .5 SheetsSheet 1 INVENTORS Dec. 14 192s. I 1,610,462

J. MATTHEWSON ET AL.-

TROLLEY HOIST Filed July 11, 1922 3 Sheets-Sheet 2 INVENTOHS Wo- 4 7 1/; M7 (M .0 I w% WM Dec. 14,1926. 1,610,462 J. MATTHEWSON ET AL TROLLEY HO I S T Filed July' 11. 1922 5 Sheets-Sheet Patented Sec. 1 2-, 192%.

nausea JOHN MATTHEW'SON AND MILO SI-IUT'I, 10F ALLIANCE, OHIO, ASSIG-NORS TO THE ALLI- ANCE MACHINE COMPANY, OF ALLIANCE, OHIO, A CORPORATION OF OHIO.

TBOLLEY HOIST.

Application filed July 11, 1922. Serial No. 5?4,-143.

The present invention relates broadly to cranes, and more particularly to crane trolleys having improved means for operating the hoisting mechanism. 1

As shown in the patent to Kendall No. 1,148,323 of July 27, 1915, it is frequently desirable to provide crane trolleys with a plurality of hoist drums and with a plurality of operating motors. As pointed out in this patent, each of the motors is preferably sufficiently powerful to lift or lower the loadand to prevent its dropping in .case of injury to the other motor, the motors usually being series wound whereby they operate in unison.

It has been found that there are certain object-ions broadly to a construction of this character. From a practical standpoint, it is extremely difficult to so adjust the brakes provided for the motors that they will be effective for stopping the motors at exactly the same time When one of the motors overruns the other, the continued operation of the other motor is effective for producing a tremendous leverage on the gears tending to lift the gear shafts and drum shafts directly from their bearings. This frequently breaks the housing caps and causes other damage.

By the present invention these objections are entirely overcome and there is provided a crane in which the advantages of a dual motor drive are retained without subjecting the bearings to any undue strain.

In the accompanying drawings, there is shown for purposes of illustration only, one embodiment of the present invention, it be ing obvious that the drawings do not define the limits of our invention and that changes may be made in the construction and operation without departing from the spirit of the invention or scope of our broader claims.

In the drawings,

Figure 1 is a top plan view of an apparatus constructed in accordance with the present invention;

Figure 52 is a side elevation of the construction illustrated in Figure 1;

Figure 3 is a detail view, partly in section and partly broken away, illustrating one of the driving connections, and

Figure 4 is a sectional view on the line IVIV of Figure 3, the shaft being shown in elevation.

Referring to the accompanying drawings there is illustrateda cranescomprising a supportingframe 2 of any desired construction having mounted therein a plurality of hoist.- ing drums 3. These drums may be inter geared by providing'centra-l gears 4, or in the manner illustrated in the patent referred to. At each end of the frame there is provided a motor 5 which motors may advantageously be of the series wound type. Each of the motors is provided with a driving pinion 6 adapted to drive the drums .3 in the desired direction through intermediate shafts 7 and 8 journaled in the frame and provided with suitable gear trains. Each of the motors is also provided with an electrically opera-ted brake 9 of any usual construction whereby the rotation of the motors may be checked, as required.

Then it is desired to hoist a load by the crane, the motors 5 will be operated in such manner as .to cause rotation of the various parts of the apparatus in the direction indicated by the arrows in Figure 1. Ordinarily both of the motors will be simultaneously operated whereby the load will be partially carried by each of the motors. This pro vides for uniformity of operation and reduces the strain on the bearings to a minimum. If the operation of the motors is checked by applying the brakes, it is obvious that one of the motors may stop before the other. In this case, the motor which overruns exerts a tremendous leverage tending to lift the hoisting drum nearest thereto bodily from its bearings. This objectionable tendency is entirely obviated by providing a slip gear connection-between each motor and its respective drum.

In Figures 3 and 4 of the drawings, there is illustrated in detail one form of driving connection which may be utilized for this purpose. As illustrated in these figures, the connection may comprise a hub 10 secured in any desired manner to each of the shafts 8 so as to rotate in unison therewith. The hub 10 has its periphery formed to provide a gear 11. Rotatably carried on the hub 10 is a gear 12 having a bearing portion 13 within the hub. This gear 12 carries a plurality of equi-distantly spaced pinions 14 carried by pins 15 extending through the hollow gear 12 and keyed thereto in any desired manner to prevent relative rotation between the pins and the gear 12. Extending transversely through suitable openings in each of the pins 15 is a pawl 6 adapted to cooperate with. teeth 17 formed interiorlv of the gears 11. This construction of well known type permitting rotation of the gears 14 in a counter-clockwise direction as viewed in Figure 3 relative to the pins 15 but preventing such movement in the opposite direction.

With the construction described, it will be assumed that the motors 5 are rotating the drums 3 in a direction to lift the load. The driving connection illustrated in Figures 3 and 4- may be considered as the connection provided for the shaft 8 adjacent the right hand end of the frame 2 as viewed in Figures 1 and 2. It will be apparent that power is transmitted from the shaft 7 to the gear 12 in a direction tending to rotate the same as indicated bythe arrow A in Figure 3. This will move all of the pins 15 bodily in the same direction thereby tending to ro tate the pinions 1 1 in a clockwise direction as viewed in Figure 8, due to their engagement with the gear 11. As rotation in this direction is prevented by the pawls 16, the gear 11, and through it the shaft 8, will be rotated in unison with the gear 12. Both of the driving connections between the shafts 7 and 8 are of similar construction and adapted to provide a positive driving connection effective during the hoisting operation.

During the hoisting operation, assume that the brakes are applied to the armature shafts of the motors. If the brake 9 cooperating with the motor 5 illustrated on the right hand end of the frame in Figures 1 and 2 is more effective than the brake cooperating with the other motor, it will be apparent that the right hand shaft 7 will be held against further rotation while all of the remaining shafts will tend to rotate under the influence of the other motor. The continued rotation of the right hand shaft 8 in the direction indicated by the arrow will tend to rotate the gear 11 in a clockwise direction, as viewed in Figure 3. This will effect rotation of. the pinions 14; in a counterclockwise direction, as viewed in this figure, thereby permitting relative movement between the gears 11 and 12. Thus the over running motor may continue to operate the hoisting drums until its brake becomes effective for stopping the rotation thereof.

While the driving connections between the respective shafts 7 and 8 might be such as to permit unrestricted movement in one direction, they are preferably such that a frictional driving engagement in the release di rection is provided. Such a connection is frequently desirable where the load being handled is not of itself sufficient weight to effect rotation of the drums. Such a frictional driving engagement may be provided by forming each of the hubs 10 with a friction surface 18 adapted to cooperate with a ring 19 of friction material. This ring may normally be urged against the friction surface 18 with a predetermined pressure by a thrust member 20 having a plurality of arms 21. Cooperating with each of the arms is a compression spring 22 tending to draw the thrust member in a direction effective for maintaining a frictional engagement between the ring 19 and the surface 18. This engagement may be adjusted by adjusting the clamping nuts 23 as will be readily apparent.

It will be apparent that the driving connections provided are effective for positively transmitting power when operated in a direction to raise the load, but permitting slippage between the motors and the drums when operated in a direction for lowering the load. In other words, during the lower ing operation, each of the motors may run ahead of its respective driving connection while during the load raising operation, each of the driving connections will move in unison with its respective motor until the motor is stopped. After stoppage each driving connection may run ahead of its respective motor.

The advantages of the present invention arise from the provision of a crane operating mechanism in which the strain on the bearings is reduced to a minimum and the operation with a plurality of motors is greatly facilitated.

We claim:

1. In a crane, a hoisting drum, and a plurality of drum actuating motors, each of said motors having a driving engagement with the drum which is positively operable in one direction and frictionally operable in the opposite direction, substantially as described.

2. In a crane, a plurality of hoisting drums, ant. a plurality of drum actuating motors, each of said motors having a driv ing engagement with the drums which is positively operable in one direction and frictionally operable in the other direction, substantially as described.

3. In a trolley hoist. a plurality of inter-- geared hoisting drums and a plurality of drum actuating motors, each of said motors having an individual driving engagement with the drums operable in both directions, the drive in one direction being suiiicient to raise the load, the drive in the other direclUO tion being a frictional one, and insuificient friction-ally operable in the other direction, to sustain the load substantially as described. substantially as described.

4. In a crane, a plurality of intergeared In testimony whereof We have hereunto 10 hoisting drums, and a plurality of drum acset our hands. 5 tuating motors, each of said motors having a driving engagement With the drums Which JOHN MATTHEWSON. is positively operable in one direction and MILO SHUTT.

Images